With higher and higher requirement of people on function and appearance of a mobile terminal, the appearance and production of a mobile terminal become more and more exquisite. At present, the most obvious change of a mobile terminal is that the past keypad is gradually replaced by a touch screen. However, despite this, the increasing aesthetic demand of a user is not satisfied; therefore, the current manufactured mobile terminal is equipped with as few keys as possible or not equipped with key at all.
Currently, most mobile terminals with touch screen mainly include a home key, a power-on key, several function keys at side of the mobile terminals, and so on. However, these mobile terminals usually start a system through an entity power button; the specific method is that: an entity power button is connected with a Power Management Unit (PMU); the PMU will be triggered after long press of the entity power button, and a Main Control Unit (MCU) is powered through the PMU, so as to maintain normal running of the MCU, thus, to complete start-up of a terminal system; when powering off, it is implemented by long press of the entity power button. But, using an entity power button to power on or off a mobile terminal makes the structure of the mobile terminal not simple enough, and can not bring better use experience to a user.